Apparatus for backing slide fastener elements



N; A. WAHL 2,909,025

APPARATUS FOR BACKING SLIDE FASTENER ELEMENTS Oct. 20, 1959 Filed Aug.18, 1954 INVENTOR. [Vic/1 alas A. I/l ahl ATTORNEY United States PatentAPPARATUS FOR BACKING SLIDE FASTENER ELEMENTS Nicholas A. Wahl, NewYork, N.Y., amignor to Wahl Brothers, New York, N.Y., a partnershipApplication August 18, 1954, Serial No. 450,703

8 Claims. (CI. 57-10) ter. Slide fasteners are broadly of two types. Onetype 1 is that 'which comprises generally a row of substantiallyparallel spaced links or coupling elements, each link or couplingelement being secured at one end to a runner or cord, and the links orcoupling elements together with the runner constituting a stringer. Thefree ends of the links or coupling elements are adapted for interfittingengagement with the links or coupling elements of a second stringer; anda slider is provided for effecting the engagement and disengagement ofthe stringer elements.

Another type of separable fastener is that which employs helicoidstringers wound for interfitting engagement with each other, asdisclosed in my prior United States Patent No. 2,300,442, and also shownin my United States Patents Nos. 2,541,728 and 2,541,729.

The last two patents and my copending application for United Statespatent entitled Method and Apparatus for Making Separable Fasteners,bearing Serial Number 418,491, filed March 25, 1954, relate to means formaking such helicoid stringers.

In this type of fastener like portions of all convolutions or loops ofthe helicoid stringers serve as links or coupling elements, and otherlike portions of all convolutions or loops constitute the equivalent ofthe runners or cords of the link-type fastener. While the apparatus ofthe present invention has been primarily developed and employed inconnection with the type of separable fasteners having helicoidstringers, and will be described hereinafter with particular referencethereto, it will be understood that the novel features of the inventionare equally well suited for use in connection with the linktypefastener.

More particularly, the present invention embraces improvements in themeans for securing a helicoid stringer to a base disclosed in my UnitedStates Patent No. 2,586,891, wherein the securement of a helicoidstringer to a base involved a sewing operation in which it was necessaryto pass a needle between adjacent convolutions of the stringer.Obviously, to produce the product shown in the cited patent, perfectsynchronization of movement is required between the helicoid stringerand the sewing needle to prevent the latter from striking convolutionsof the former and to effect securement, by lashing stitches, of eachconvolution to the base or backing member; and, further, the smallesthelicoid stringer and base assembly available is limited by the size ofthe needle, as the latter must be able to pass between adjacentconvolutions. In addition, the constructions and methods of the priorart required two separate sewing 2,909,025 Patented Oct. 20, 1959operations to attach the two stringers desired to form part of a singlefastener to two separate tapes; and it was necessary to disengage thetwo stringers during the attaching operations, which served to increaselabor costs and to produce misregister of the coupling elements of thetwo stringers due to elongation and other deformation thereof.

The present invention, which is illustrated in the drawing, and whichwill be described hereinafter in greater detail, contemplates apparatusfor attaching a base to a helicoid stringer by a process of windingwhereby a sewing operation at this stage in the manufacture of separablefasteners is ob'viated.

By means of the apparatus of the invention the base is built orfabricated upon the stringer in such manner that a helicoid stringer ofminute proportions may be provided with a base or backing member, or, infine, a fabric attached to and paralleling the stringer along one sidethereof and through which a sewing needle may subsequently beconveniently passed for the purpose of securing the stringer and baseassembly to a suitable tape. Further, by means of the present apparatusa stringer and base assembly may be made at relatively high speed.

A form of the apparatus adopted for the purpose of illustrating theinvention in the drawing is adapted for lashing a cord or the like tothe outside of and parallel to the stringer by means of one or morefilaments wound around the cord and around consecutive like portions ofthe convolutions of the helicoid stringer. Of course, while both thecord and the lashing filaments constitute the base or backing member, itwill be understood that the cord, which may be of sufiicient thicknessto facilitate the subsequent sewing operation when the stringer and baseassembly is attached to a tape, is, for practical purposes, the sewablebase, for the lashing filaments may be extremely fine threads. However,the apparatus as illustrated may operate to form a base along theoutside of the stringer, the base comprising solely what would have beenthe lashing filaments had a cord been present. In such case, of course,the filament or fila ments wound around consecutive like portions of theconvolutions of the helicoid stringer should be of sufficient thicknessto provide an easily sewable base.

The present apparatus is adapted to operate in association with a pairof stringers which may be fed toward the apparatus in interfittingengagement, separated in usual manner, and, after the application of abase to each of the stringers, rejoined, so that the resulting productis an interfitted pair of stringers with bases attached to the outsidesof the pair. Thus an advantage of the invention is that a pair ofstringers in interfitting engagement and provided with oppositelydisposed bases may be united with the articles to be separably fastenedat relatively high speed by means of a two-needle sewing machine orother multiple securing device which may be employed to unite thestringers in their engaged relationship with such articles. As nosynchronization is required between the stitching and the convolutionsof the stringers, a sewing machine may operate at extremely high speedto effect a considerable saving in time in completing the fastener.Relative deformation or other misrregister of the stringers is obviated,and perfect matching thereof is maintained.

Further, as the stringers are firmly secured to their bases there ispractically no likelihood of the stringers twisting and presenting theirnon-meshing portions toward each other, as frequently occurred in priorart constructions.

For convenience herein those portions of the convolutions of a helicoidstringer to which the base is attached are regarded as being on theoutside of the stringer; and, conversely, those other portions whichoperate as links or coupling elements in the finished fastener areregarded as being on the inside.

Other objects, features, and advantages of the present invention will bemore fully understood from the following detailed description, and fromthe drawing, in which, for purposes of clarity, some parts are showngreatly enlarged and somewhat exaggerated.

In the drawing:

Fig. 1 is an elevational view of one embodiment of the invention; Fig. 2is the section 2-2 of Fig. 1, and Fig. 3 is a perspective 'view of apart of an apparatus showing the inventive device included therein.

It has been suggested above that the apparatus is adapted to operate inassociation with a pair of stringers originally in interfittingengagement, which, after separation in usual manner, may each beprovided with a base, and then rejoined to produce a pair ofinterfitting stringers with bases attached to the outsides of the pair.However, the embodiment of the invention shown in the drawing is suitedfor applying a base to a single stringer, and

where it is desired toapply a base to each of two separate stringerssubsequently to be joined together in interfitting engagement, and toapply the bases simultaneously, two of such embodiments, or theequivalent, are required; and, also, two winding or braiding machinesare required, the two embodiments and the two machines being in timedrelationship to each other. It will be further understood from thefollowing brief description of the structure of a pair of separablehelicoid stringers adapted for interfitting engagement, as disclosed ingreater detail in United States Patents Nos. 2,300,442, 2,541,728, and2,541,729, and in my copending application for United States patentbearing Serial Number 418,491, filed March 25, 1954, all mentionedabove, that the two embodiments required for work with a cooperable pairof stringers may be either exact duplicates, or mirror images of eachother, depending upon the relative directions of rotation of theassociated winding or braiding machines. If the machines are directlygeared together for opposite directional rotation, the embodiments wouldordinarily be mirror images of each other. If, for example, an idlerwere employed in coupling the machines, the embodiments might well beexact duplicates.

The cooperable helicoid stringers of a pair forming part of the secondtype of separable fastener mentioned in the preamble hereto arepreferably two oppositely directed, but otherwise similar, slightlyflattened coil-like elements formed of like filaments of material whichmay be permanently set as helicoids. While the cross section of thestringer, as an entity, may be circular, it has been found moreconvenient in the manufacture of the complete separable fastener thatthe cross section be elliptical,

, for such cross section facilitates the application of bases to thecooperable stringers with less interference with the coupling elementsthereof.

A particular feature of the filament employed for forming the helicoidsis that its width is greater than its thickness. For example, the crosssection of the filament itself may 'be, and preferably is, substantiallysimilar to a half circle, whereby the filament has a longitudinallyextending fiat surface. If the cross section of the filament employed issubstantially similar to a half circle, the width of the filament isthen about twice the thickness thereof. Accordingly two filaments may bewound in staggered relationship to each other around a mandrel the crosssection of which is elliptical or otherwise oblong, with thelongitudinally extending fiat surfaces of the two filaments in contactwith the mandrel and thereby preventing rotation of the filaments alongtheir lengths; and, if the filaments, while in the inter-fittingengagement resulting from so winding them, are set (e.g., as byheattreatment) in their resulting helicoid forms, the two helitionthereof, only by stretching the pair of helicoids to time theirinterlocking convolutions for sidewise movement away from each other. Inshort, where two such helicoids form part of a separable fastener, thefunction of the slider, already mentioned, is alternately to free theinterlocking helicoids by progressively bending them away from eachother, the equivalent of slightly elongating the helicoids at successivestations of position and simultaneously guiding the freed convolutionssidewise out of engagement with each other, and to rejoin the helieoidsin interfitting engagement by a reversal of such process.

The apparatus of the invention is adapted to operate as an attachmentfor, or in association with, a conventional winding or braiding machine.Only those parts of such a machine necessary to an understanding of thepresent invention are shown in Fig. 3. Thus, there is a table 2 having araceway 3 therein, which raceway is circular about the center of thetable. Posts 4 and 5 travel in such raceway, driven therein by knownmechanism, not

'shown,andmounteduponeachpost4and5is aspool6 and 7 respectively, eachcarrying a supply of thread or other filament. At the center of thetable .2 a cylinder is fixedly mounted, as by threading or welding, inan aperture 8 in such table 2, the aperture being enlarged at 9 topermit passage therethrough of a helicoid stringer.

The fixed cylinder is indexed 10, and has a longitudinal, groove 11along one side thereof, and two staggered helices '12 and 13, both woundin the same direction and freely surrounding the cylinder for rotationtherearound.

The helices 12 and 13 may be formed of wire or other suitable materialwhich may be set in the form illustrated.

One end portion of the material of helix 12 extends tangentially awayfrom the cylinder near the lower end thereof, and this tangentiallyextending portion is designated 14. One end portion of helix 13 alsoextends tangentially away from the cylinder near the lower end thereof,and this last named tangentially extending portion is designated 15. Itwill be seen in Figs. 1 and 2 that the portions 14 and 15 of helices 12and 13, respectively, extend away from the cylinder in oppositedirections. Each of these portions 14 and 15 is secured, in suitablemanner, to posts 4 and 5, respectively. Accordingly, as the spoolcarriers travel around their common circular path the two helices v12and 13 are rotated around the cylinder ll.

The upper end portions of the material of helices 12 and 13 are bent toform simple thread or filament guides 16 and 17, respectively. Guide 16is associated with a thread or filament l8 drawn from spool 6, and guide17 isassociatedwithathreadorfilamentfldrawnfrom spool 7.

The cylinder 10 is longitudinally bored from end to end, as indicated bythe reference numeral 20, and the top portion 21 of the bore is flaredso that but an exceedingly thinwall22remainsbetweentheupperendoftheboreandthedeepestpartofthelongitudinal groovell of cylinder 10.

A helicoid stringer 23 is seen in the drawing, and its direction oftravel through the apparatus and aperture enlargement 9 is upward. Across section of the helicoid is seen in Fig. 2. Here what has beenreferred to above as the outside of thestringer is carried partly withinthe longitudinal groove 11; and helicoid stringer is maintained inengagement with the groove by means of the helices 12 and 13, which passbetween alternate pairs of convolutions of the stringer, as best seen inFig. 1. It will be quite obvious from the drawing that as the windingmachine operatm and etfects rotation of helices 12 and 13 these last twoelements togetheroperate as a feed screw to carry the helicoid stringerupwardly through the apparatus.

Passed through the bore 20 of cylinder 10 is a cord 24 which is ofsuflicient thickness to serve as an easily sewable base for thestringer. At the flared top portioncoidsmaythereafterbeseparatedwithoutlitenldesuuc- 21 of the borethecord24iscarriedover into contact with the outside of the stringer by theactions of threads or filaments 18 and 19 which are respectivelydirected by guides 16 and 17 between alternate pairs of convolutions ofthe stringer, and, as a resultof the operation of the winding machine,lash the cord 24 to the successive convolutions of the helicoid on theoutside thereof, as shown.

It will be understood that the scale of the drawing is greatly enlarged,but this fact in no way affects the essence of the invention. Ordinarilya stringer of the type shown would be very small in cross section,possibly even less than one sixteenth of an inch. Further it will beunderstood that the helices 12 and 13, both as to cross section of theirfiliform material and as to pitch, are required to conform to theparticular size and character of stringer to be handled by them. Wherethe stringer is of minute size the helices 12 and 13 may be wires ofhigh gage, and therefore very resilient. However this has been found tobe immaterial as the intermeshing of the helices with the convolutionsof the stringer has remained undisturbed under ordinary operatingconditions even where minute filament cross sections were involved, forthe more stablehelicoid stringer actually operates to preserve thedistribution of the convolutions of the feed helices. It is recommendedthat a detent, such as a collar fixed with relationship to the cylinder,and at the top thereof, or above, be provided to counteract against anytendency of the feed helices to progress axially with respect to thecylinder during their rotary movement therearound.

From the foregoing it will be understood that a single feed helix couldbe adapted to serve in place of the pair designated 12 and 13, providedthe pitch of the single helix were 50% of that of either of thosedescribed. Similarly, the helicoid stringer might well be fed along thecylinder by means of a cylindrical matrix revolving around the cylinder10, the matrix having suitable internal threads like a nut. In thelatter case a filament may be brought into engagement with the helicoidstringer and the cord, if the latter is desired to be used, through asuitable opening in the matrix, which, of course, would revolve with thewinding machine.

I claim:

1. In apparatus of the class described, a fixed cylinder having alongitudinal groove along one side thereof; means cooperating with saidcylinder for feeding a stringer of slide fastener elements along saidgroove and partly within the same; means for feeding a cord to saidstringer of slide fastener elements, and a supply of filament traversinga fixed orbit around said cylinder, in timed relationship with saidmeans, for winding filament around said stringer and between theelements :thereof as the latter pass beyond an end of said cylinder.

2. In apparatus of the class described, a fixed cylinder having alongitudinal groove along one side thereof and a longitudinal holethrough said cylinder; means cooper+ ating with said cylinder forfeeding a stringer of slide fastener elements along said groove andpartly within the same; a cord passed through said hole; and a supply offilament traversing a fixed orbit around said cylinder, in timedrelationship with said means, for winding filament around said stringerand between the elements thereof as the latter pass beyond an end ofsaid cylinder, and for lashing said cord to said stringer, whereby theadvance of said stringer draws cord through said hole.

3. In apparatus of the class described, a fixed cylinder having alongitudinal groove along one side thereof; means cooperating with saidcylinder for feeding a helicoid stringer of slide fastener elementsalong said groove with certain parts of consecutive convolutions of saidstringer partly within said groove; means for feeding a cord to saidstringer of slide fastener elements, and a supply of filament traversinga fixed orbit around said cylinder, in timed relationship with saidmeans, for winding filament around said certain parts of saidconvolutions and between said elements as the latter pass beyond an endof said cylinder.

4. In apparatus of the class described, a fixed cylinder having alongitudinal groove along one side thereof and a longitudinal holethrough said cylinder; means cooperating with said cylinder for feedinga helicoid stringer of slide fastener elements along said groove withcertain parts of consecutive convolutions of said stringer partly withinsaid groove; a cord passed through said hole; and a supply of filamenttraversing a fixed orbit around 'said cylinder, in timed relationshipwith said means, for winding filament around said certain parts of saidconvolutions and between said elements as the latter pass beyond an endof said cylinder, and for lashing said cord to said certain parts ofsaid convolutions, whereby the advance of said stringer draws cordthrough said hole.

5. In apparatus of the class described, a fixed cylinder having alongitudinal groove along one side thereof; a helix surrounding saidcylinder and rotating therearound in mesh with the consecutiveconvolutions of a helicoid stringer of slide fastenerv elements adjacentsaid groove with certain parts of said convolutions within said groovefor feeding said stringer along said groove; means for feeding a cord tosaid stringer of slide fastener ele ments, a supply of filamenttraversing a fixed orbit around said cylinder for winding filamentaround said certain parts of said convolutions and between said elementsas the latter pass beyond an end of said cylinder; and an elongatedmember extending radially from said helix and being fixed to an endthereof and engaging part of said supply of filament for rotationthereby.

6. In apparatus of the class described, a fixed cylinder having alongitudinal groove along one side thereof and a longitudinal holethrough said cylinder; a helix surrounding said cylinder and rotatingtherearound in mesh with the consecutive convolutions of a helicoidstringer of slide fastener elements adjacent said groove and withcertain parts of said convolutions within said groove for feeding saidstringer along said groove; a cord passed through said hole, a supply offilament traversing a fixed orbit around said cylinder for windingfilament around said certain parts of said convolutions and between saidelements as the latter pass beyond an end of said cylinder, and forlashing said cord to said certain parts of said convolutions, wherebythe advance of said stringer draws cord through said hole; and anelongated member extending radially from said helix and being fixed toan end thereof and engaging part of said supply of filament for rotationthereby.

7. In apparatus of the class described, a fixed cylinder having alongitudinal groove along one side thereof; a helix surrounding saidcylinder and rotating therearound in mesh with consecutive coupled slidefastener elements of a stringer thereof adjacent said groove withcertain parts of said elements within said groove for feeding saidstringer along said groove; means for feeding a cord to said stringer ofslide fastener elements, a supply of filament traversing a fixed orbitaround said cylinder for winding filament around said stringer andbetween the consecutive elements thereof as the latter pass beyond anend of said cylinder; and an elongated member extending radially fromsaid helix and being fixed to an end thereof and engaging part of saidsupply of filament for rotation thereby.

8. In apparatus of the class described, a fixed cylinder having alongitudinal groove along one side thereof and a longitudinal holethrough said cylinder; a helix surrounding said cylinder and rotatingtherearound in mesh with consecutive coupled slide fastener elements ofa stringer thereof adjacent said groove with certain parts of saidelements within said groove for feeding said stringer along said groove;a cord passed through said hole; a supply of filament traversing a fixedorbit around said cylinder for winding filament around said stringer andbetween the consecutive elements thereof as the lat- V 7 ter pass beyondan end of said cylinder, and for lashing said cord to said stringerbetween said elements, whereby the advance of said stringer draws cordthrough said hole; and an alongated member extending radially from saidhelix and being fixed to an end thereof and engag- 5 ing part of saidsupply of filament for rotation thereby.

References Cited in the file of this patent UNITED STATES PATENTS 7,571Batty Aug. 20, 1850 8 Champlin June 26, 1906 ResPess Nov. 8, 1924 BondOct. 26, 1937 Wahl Feb. 13, 1951 Wahl Feb. 13, 1951 Neale Apr. 15, 1952Stanford Feb. 9, 1954

